title: Medical image. Mediastinal air-fluid level with substernal pain: achalasia.
authors.forename: Prem P
authors.initials: PP
authors.lastname: Gupta
authors.forename: Rohtas
authors.initials: R
authors.lastname: Yadav
authors.forename: Dipti
authors.initials: D
authors.lastname: Agarwal
authors.forename: Krishan B
authors.initials: KB
authors.lastname: Gupta
mesh_terms: D002637:Chest Pain / Q000000981:diagnostic imaging* / Q000209:etiology; D004931:Esophageal Achalasia / Q000150:complications / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008875:Middle Aged; D011859:Radiography